1. Field of the Invention
The present invention relates to a medical prosthesis for human implantation, and in particular, to a biological wound dressing for protecting a wound surface during wound treatment.
2. Description of the Prior Art
The human body itself is equipped with a perfect repair mechanism for wounds so that many moderate and small wounds can heal themselves by the body's inherent repair system if the wound surface is protected from infections. In general, the treatment of an external wound includes first cleaning and then sterilizing the wound surface, followed by protecting the wound surface with a wound protective dressing to prevent post-infection. Accordingly, a fast development pace has been seen in recent years for protective dressing materials, and various protective wound dressings have been marketed.
However, these protective materials are mostly films of synthetic materials, such as silicone rubber gel film, polyamide film, nylon film, Dacron film, polyethylene film, polypropylene film, etc. These synthetic materials have gradually been found to have poor tissue compatibility and unsatisfactory treatment effect after being used for a certain period of time.
Accordingly, some scientists have attempted to prepare wound dressings using natural biological materials such as collagen, but collagen has poor mechanical strength and requires reinforcement with synthetic film. Such collagen and synthetic material composite films have improved tissue compatibility, but the flexibility is reduced due to increased thickness, and also suffer from poor gas permeability and poor application property.
Some scientists have also utilized chitin and chitin-collagen composite materials to produce protective films, but these films also suffer from poor mechanical strength, poor durability, and poor flexibility, and have not been widely applied.
Pig skin has also been utilized to produce wound dressings in recent years, but the treatment techniques are confined to the traditional glutaraldehyde fixation and chrome tanning method without special treatment for elimination of antigens, thereby exposing the patient to residual toxicity and potential rejection reactions resulting from incomplete elimination of antigens. Such pig skin products also exhibit poor flexibility with enlarged pores after drying so that the bacterial barrier property is poor, and the application property and treatment effect are not ideal, which limits their wide use and application.
Pig small intestine submucosa (SIS) has also been utilized to produce wound dressings, but the treatment used for antigen elimination is a cellular removal technique. However, the protein in the tissue still has remaining antigenicity because antigen determinants exist in many specific sites and their specific conformations. Although the outcome of the acellular SIS based wound dressing is acceptable, there are still improvements that need to be made.